STUDIES IN THE ENZYME MAKE-UP OF ALTERNARIA. 8. PECTIC ENZYMES.

Abstract

Present studies indicate that all the three species ofAlternaria possessed both intra- and extracellular PME activity but only the latter was significant. The role of the enzyme in pathogenicity of the strains has been discussed. The various optima determined for the extracellular enzyme activity were pH 4.5–7.0, temperature 50° C, time 24 hrs, and substrate concentration 1% pectin; the activity was proportional to enzyme concentration. Of the chemicals used to characterise the properties of the enzyme Na2HPO4, NaH2PO4, Mg++, Ca++ produced marked activation.